I'm not sure if this has ever been implemented yet, but can you imagine a way of paying with Bitcoin by just using your own body?
How about ur wallet, physical wallet? Why going to blood & gore stuff if u don't need too?
I don't like idea of implants, its too physical when its no reason to.
We already have physical wallets devices like trezor and keepkey, ledger for smaller screenless size. Seems like this is already here and being used.